Forced air heating system



June 6, 1961 J. E. NORTH FORCED AIR HEATING SYSTEM 3 Sheets-Sheet 1 Filed Oct. 9, 19-57 INVENTOR. James fflfoz'zfz June 6, 1961 J E. NORTH 2,987,258

FORCED AIR HEATING SYSTEM Filed Oct. 9, 1957 3 Sheets-Sheet 2 W-mm m im m H 1- INV EN TOR.

rfazzzw I/Vorifi June 6, 1961 J. E. NORTH FORCED AIR HEATING SYSTEM 3 Sheets-Sheet 3 Filed Oct. 9, 1957 U e St e PM 2,987,258 r FORCED AIR HEATING SYSTEM James E. North, Park Forest, 111., ass'ignor, by mesne assigninents, to Heil-Quaker Corporation, a corporation of Delaware Filed Oct. 9, 1957, Ser. No. 689,132 4 Claims. (Cl. 237-53) The invention relates to central heating systems generally and more particularly to heating systems of the forced air type.

One object of the invention is to provide a plenum chamber and blower assembly in the form of a simple compact structural unit particularly well adapted for economical quantity production and distribution by reason of its ready adaptability on the job for use in heating systems varying widely in respect to the type of heater employed, the rooms to be heated and the number and location of the ducts required, and by reason of the flexibility afiorded for expansion of the heating system after installation to supply heat to additional rooms.

.Another object is to provide a plenum chamber and blower unit that may be connected directly to a suitable .heater or simply installed in the ceiling of a room heated by a conventional space heater to adapt the same for 'heating a plurality of rooms.

blower unit in which the blower and its driving motor are mounted in a novel manner to insure adequate ventilation and adequate cooling of the motor.

Other objects and advantages of the invention will become apparent from the following detailed description of the preferred embodiment illustrated in the accompanying drawings in which:

FIGURE 1 is a perspective view of a plenum chamber and blower unit embodying thefeatures of the invention, the unit being shown installed in a room ceiling andlarranged for direct connection with a heater.

FIG. :2 is a perspective view of a complete heating syst'emutilizing the improved unit, the heat source in this instance being a conventional space heater.

FIG. 3 is a sectional view taken in a vertical plane through the plenum chamberand the building structure in which it is mounted.

FIG; 4 is a fragmentary elvational view of the chamber structure showing the manner in which the wall-is prelimi'narily formed to define the duct openings.

FIG. 5 is a sectional view taken in a vertical plane substantiallyon the line55 of FIG. 4.

FIG. '6 is an elevational view similar to FIG. 4 but showin a section 'of the chamber wall removed to define a 'duct'outlet, the removed section being installed to function as a damper for the outlet.

1 FIG. 7 is a sectional view taken in a vertical plane substantially on the line 7 7 of FIG. 6.

For purposes of illustration a preferred embodiment of the invention has been shown and will be described herein in some detail. It will be understood, however,

"that this is not intended to limit the invention to the particular structural details disclosed. On the contrary, the intention is to cover all modifications and adaptations falling within the spirit and scope of the invention as defined in the appended claims. 7 V

By way of example, the invention has been shown in 2,987,258 Patented June 6, 1961 ice FIGS. 1-3 as incorporated in a structural unit 10 for adapting an ordinary room space heater 11 for efficiently heating a plurality of rooms. As shown in FIG. 2., the space heater is installed in one room 12 of a house 13 and operates in the usual way to heat that room by convection and radiation. The unit 10 which is preferably installed in the ceiling 14 of the room 12, draws heated air from that room and forcibly distributes it to other rooms 15 of the house.

Under some conditions, it may be desirable to connect the unit directly with the heater. Such connection is provided by a suitable duct 16 extending upwardly from the heater to the unit as shown in FIG. 1. With either direct or indirect connection of the unit, passages 17 are provided between the rooms 15 and the room 12 for the return of cold air, thus afiording continuous air circulation through the entire house and materially improving the operating eificiency of the heating system.

The structural unit 10 includes a housing 18 which may be constructed of any suitable material, although sheet metal is preferred for economical fabrication. In the preferred form shown, the housing comprises a boxlike sheet metal structure divided internally into two compartments by a partition 20. One compartment 21 constitutes the inlet chamber while the other constitutes a distributing or plenum chamber. The chamber 21 is adapted to communicate with the space from which heated air is to be drawn, in this instance, through an opening 23 in the bottom wall of the housing. A motor driven blower 25 draws heated air through the opening into the chamber 21 and discharges it into the plenum chamber 22 from which it is distributed to the rooms 15 by way of ducts 26. In the heating system shown in FIG. 2. the ducts are shown terminating in ceiling fixtures in the rooms 15, although it will be understood that they may open through the walls or even through the floor of a room if desired.

In the particular embodiment shown, the housing 18 is L-shaped in horizontal section. It has one straight side wall 27, one long end wall 28 and one short end wall 29. The other side wall 30 is stepped, that is, it has one end portion ofiset from the other an amount corresponding to the difierence in length of the end walls 28 and 29. It is thus adapted to be assembled with the other wall elements to form the boxlike structure shown in FIG. 1.

A sheet metal top panel 31 extends over and covers both of the compartments in the housing 18. This top panel may be formed with flanges adapted to fit over the upper end of the housing and is preferably secured in place in a manner which permits easy removal to provide convenient access to the interior of the housing. A similar bottom panel 32 closes the lower end of the housing, apcrtion of the panel being cut out to provide the opening 23 to the inlet chamber 21.

The partition 20 which divides the housing 18 into the two compartments 21 and 22, is L-shaped in the exemplary unit. It is assembled with the other components of the housing 18 to form a rectangular compartment at one corner of the housing, that being the intake chamber 21 in the present instance. The longer leg of the L-shaped partition is substantially the same length as the inwardly offset portion of the side wall 30 which it parallels. The other leg of the partition is substantially the same length as the offset of the portions of the wall 30 and is directed oppositely to such offset. The partition mus cooperates with the walls of the housing to define the T-shaped plenum chamber 22.

The unit it? may be supported in any preferred manner, as, for example, by angle bars 33 extending across a plurality of the joists 34 which support the ceiling 14. It will be understood, of course, that the unit is positioned with the bottom opening of the chamber 21 in alinement with a hole cut through the ceiling. When the unit is connected directly with the heater as shown in FIG. 1, the duct 16 extends through the hole in the ceiling and its upper end is suitably attached to the bottom wall 32 of the housing structure. When the unit is installed in a 'ceiling'without direct connection to the heater, the ceiling hole may be finished off with a liner 35 carrying an adjustab'le shutter or damper mechanism 36 as shown in FIG. 3.

While a blower of any suitable type may be utilized for drawing air into the inlet chamber 21 and discharging it into the plenum chamber 22, the blower 25 of the exemplary unit is a centrifugal fan type blower. It includes a multi-bladed fan wheel 36 mounted for rotation in a generally spiral casing 37. The casing has an air inlet opening coaxial with the fan wheel and in this instance alined with an opening 38 formed in the partition 20. The outlet for the fan is preferably located adjacent the end of the narrow leg section of the plenum chamber '22 and positioned to discharge into the transverse head portion of the chamber.

The fan wheel 36 of the blower is rotatably driven by an electric motor M, and, in this instance, is mounted directly on the motor shaft. As a matter of convenience, the motor is supported on the outside wall of the housing structure which parallels the partition or on a suitable frame provided on or adjacent such wall. To insure cool running, the motor is preferably located externally of the housing structure with its shaft extending through a hole 39 in the wall 30. The motor is thus out of the stream of heated air moved by the blower. As the unit is usually installed in an attic or other unheated space, overheating during the time the heating system is in operation is avoided. Additionally, forced air ventilation of the motor may be provided if desired by enlarging the hole 39 to enable the motor to draw cool outside air through the motor housing.

As indicated heretofore, heated air is distributed from the plenum chamber 22 to the rooms to be heated by the ducts 26 leading from the chamber. The number of such ducts required may vary for different installations, depending upon the number of rooms to be heated. To enable a single, standard structural unit to be used for any of the diverse installations likely to be met with, the housing structure is manufactured and supplied to each job without duct openings. Such openings are defined, however,

the wall to be removed to form the duct openings. In

the installation of a unit, the partially cut wall sections ciated that provision may be made for installation of more or less than that number of ducts. Thus, as shown in 'FIG. 1, knockout sections 40 are provided in each olfl the side walls 27 and 30 of the chamber 22 and two knockout sections 40 are provided in the end wall 28. In the preferred form of construction shown, the removable wall sections 40 are preliminarily outlined by four arcuate slits '41 arranged to define a. circle as shown in FIG. 4. The ends of the slits are spaced apart, leaving integral tongues 42 connecting the sections with the remainder of the wall and holding them in place. The tongues 42 are "relatively narrow so that they can be broken off when necessary by application of pressure or a sharp blow to :theoutlined wall section. H i 1 n by slits or cuts stamped or otherwise formed in the walls of the plenum chamber partially outlining sections 40 of 2,987,258 V i I.

4 V In accordance with another aspect of the invention, the unit is constructed and arranged to adopt each wall section 40 for use as an adjustable damper for the duct outlet which is originally closed. For this purpose, each wall section 40 is formed with a hole 42 and the adjacent portion of the wall is formed with a hole 43 for the reception of a bolt 44 for pivotally mounting the section 40 on the housing wall. The holes are located so that the sec tion 40 when mounted on the pivot bolt may be swung across the opening 45 resulting from the removal of that section from the wall. In this way, the eflective area of the duct opening may be adjusted as required for any installation.

To facilitate shipping and handling of the units, it is contemplated that a pivot bolt 44 will be assembled in the hole 42 of each wall section 40 and secured in place as by welding. A nut 46 is screwed onto the bolt as shown in FIG. 5 when a unit is initially assembled. The unit may then be shipped and stored without losing any of the damper parts. When a duct is to be installed, the section 40 is pushed or knocked out and the nut removed from the bolt. The section is then remounted on the wall by engaging the pivot bolt in the hole 43 and reapplying the nut as shown in FIGS. 6 and 7. The damper thus formed may be swung about its pivot to vary the opening or efiective area of the opening 40 as required. To facilitate adjustment of the damper, the end of the pivot bolt 46 is formed with a transverse slot 47 for the reception of a screw driver blade or other tool. The slot is preferably oriented with respect to the section to provide a visual indication of the damper position after a duet has been connected to the opening. One end of the notch may be distinctively shaped, as for example, beveled, to distinguish between the full open and full closed positions of the damper.

The above features also increase the utility of the unit by affording a high degree of flexibility for expansion after installations. Thus, a system installed for initially heating one or two rooms 15 in addition to its room 12 may be quickly and easily expanded to heat an additional room or plurality of rooms. All that is required is to knock out a wall section 40 for each additional duct 26 required and to install a standard duct or sheet metal pipe. The removed section and its pivot bolt and nut are right at hand for installation as the damper. Thus,

even though the expansion may be made years after the initial installation, instant availability of the required parts is insured.

It will be apparent from the foregoing that the invention provides a structural unit of novel and advantageous character by which a conventional room space heater may be quickly and easily adapted for heating an entire house. The improved unit may be connected directly to a heater or it may be installed so as to draw air from a room heated by an ordinary space heater. The heated air, however supplied, is forcibly distributed to the. other rooms to be heated.

The improved structural unit is simple and inexpensive to manufacture. In particular, the provision of removable sections in-the plenum chamber walls to define the duct outlets permits the use of a single standard unit for wide variety of installations. In. other words, a standard unit can distribute the heat to any number of rooms within the capacity of.the heating system. Units can therefore be 'manufactured in quantity and kept in stock by contractors or others'in the heating system'field with the usual economies accruing from quantity production and distribution. I 7

The invention also provides for the mounting of the blower motor in an advantageous manner to insure cool operation at all times More particularly, the motor is mounted out of the path of the heated air moved by the blower and the latter may also function to circulate cold outside air through the motor housing.

I claim as my invention:

1. A structural unit fora heating system comprising, in combination, a boxlike structure having side and end walls, a partition dividing said structure into intake and plenum chamber, the outside walls of said plenum chamher having sections partially cut through for on the job removal to define outlet openings, and means permanently secured to the chamber walls for adjustably securing the removed wall sections to the walls in overlying relation to the openings to determine the effective areas of the openings.

2. A structural unit for a heating system comprising, in combination, a boxlike structure having side and end walls, a partition dividing said structure into intake and plenum chamber, the outside walls of said plenum chamber having sections partially cut through for on the job removal to define outlet openings, each of said sections and the adjacent portion of the wall being apertured for the reception of a bolt for pivotally mounting the section in position to swing across the opening resulting from I the removal of the section, and a pivot bolt and nut for mounting each section, said bolt being mounted through the hole in the associated section and secured thereto as by welding, said nut being screwed on the bolt in the initial assembly of the unit.

3. A structural unit for a heating system comprising a boXlike structure having at least one flat sheet metal wall, said wall being partially cut through to define circular knockout sections, each of said sections having an aperture adjacent one edge, a pivot bolt assembled in each aperture and welded to the section for bolting the section to the wall after its separation therefrom, said wall having apertures for receiving said bolts positioned to locate the sections for swinging across and controlling the effective areas of the openings formed by their separation and removal from the wall, and a tool receiving slot in the end of said bolt by which the position of a section can be adjusted, said slot being oriented relative to the section to provide a visual indication of the position of the section.

4. A structural unit for distributing air heated by a space heater to a plurality of rooms, said unit comprising, in combination, a boxlike sheet metal structure adapted to be mounted in the ceiling of a room containing a space heater, a partition dividing said structure into intake and plenum chambers, said intake chamber having a bottom opening in communication with the room containing the heater, a motor driven blower mounted on said unit in position to draw air from said inlet chamber and discharge it into said plenum chamber, the walls of said plenum chamber having a series of integral sections partially cut out for ready removal on the job to provide duct outlets from the plenum'chamber, and means carried by said sections for pivotally mounting them on the wall to swing over the duct openings resulting from their removal.

References Cited in the file of this patent UNITED STATES PATENTS 2,332,969 Higley Oct. 26, 1943 2,338,356 Powers Ian. 4, 1944 2,516,368 Coleman July 25, 1950 

